I live in NH and I have a roommate I want to get rid of. They did not sign a lease or any type of agreement. I would like to know how to get rid of them.

I guess you have to come clean and just ask him/her to leave and tell them why. If you have a roommate, one that you hardly know, you must interview them first to see if they are suitable for the purpose. If your present roommate is paying you to share rent, then I don't know how you will accomplish getting rid of them.

If the roommate doesn't have their name on the lease then, besides asking them to move out, you could also legally put their stuff outside and have the locks changed as long as they don't have mail coming in their name, because once the police are called ,if they can show something with their name on it with your address then it will become a sticky situation otherwise that's all you need to do, and I was told this by an officer on how to get people out of your homes that are not on your lease and the cops will not do anything about it if they try to call them